The Princess Royal’s 63-year-old former husband, who coaches the US eventing team, has left his second wife, Sandy, for fellow equestrian Lauren Hough, 35.

Capt Phillips, who is getting divorced for the second time, said it was “sad” that his affair with Miss Hough, who is also a member of the US team’s coaching staff, had led to calls for his resignation from some eventing fans in the US.

He is currently in London ready for the start of the equestrian Olympic events, in which his riders will be competing against his daughter, Zara Phillips, this weekend. He has already announced that he will be leaving his job with the US eventing team after that.

He told Country Life magazine: “I don’t read chat rooms and all that rubbish as it is mostly uninformed and unidentified opinion, which won’t change my life.

“I have the total support of the team and that’s what matters. I’m not out to win a popularity contest. It’s sad when a sport can’t get behind their coaches going into the Olympics, and if that’s the future, I’m not sad to be leaving.”

Capt Phillips, who has a 14-year-old daughter, Stephanie, by his 58-year-old wife, said reports that he had already bought a home in Florida with Miss Hough were wide of the mark.

“Aston Farm (his marital home in Gloucestershire) is home, England is home and, for the record, I don’t own a house in Florida and I’m not about to buy one,” he said.

“I’m going to continue working in America, but I’m looking forward to spending more time working here.”

When The Daily Telegraph broke the news of his divorce in May, one respected US eventing website described his behaviour as “reprehensible” and others called on him to quit straight away.

Capt Phillips, an Olympic gold medallist in three-day eventing, grew close to American Miss Hough through his 20-year stint as trainer of the US eventing team.

He reportedly told friends that “I might only be alive for another five or ten years so I might as well be happy”.

Born in California, Miss Hough is the daughter of another Olympian, Charles “Champ” Hough, who won a bronze medal in team eventing at the Helsinki Games in 1952.

Capt Phillips also spoke about the dilemma of coaching a team which will be competing against his daughter over the next fortnight.

“I am 110 per cent committed to helping the USA win a medal,” he said. “But if that’s not good enough, then I hope the British will be on top.

“If I can, I will watch Zara, but you’re always so busy at a championship. The American squad will have my full attention.”

Capt Phillips is likely to bump into some familiar faces if he turns out to support Zara.

The Queen, the Duke of Edinburgh, the Prince of Wales, the Duchess of Cornwall, The Duke and Duchess of Cambridge, Prince Harry and Capt Phillips’s ex-wife the Princess Royal will all pay visits to Greenwich to cheer on 31-year-old Zara during the first week of the Games.